<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
	<style type="text/css">
		*{
			margin: 0;
			padding: 0;
		}
		.nav{
			width: 100%;
			height: 50px;
			background: #000;
		}
		.center{
			width: 80%;
			margin: 0 auto;
		}
		a{
			float: right;
			color: #fff;
			width: 100px;
			text-align: center;
			line-height: 50px;
			background: #666;
			text-decoration: none;
			position: relative;
		}
		.car{
			width: 600px;
			height: 0px;
			line-height: 100px;
			text-align: center;
			position: absolute;
			background: url(https://img2.baidu.com/it/u=3967329752,2269316544&fm=253&fmt=auto&app=138&f=JPEG?w=475&h=477) no-repeat;
			border: 1px solid #ccc;
			right: 0;
			color: #ccc;
/*			display: none;*/
			/*	设置hover过度时间	  all 所有hover属性都参与进来
				0.3表示过渡时间
				*/
			transition: all 0.3s;
			/*		溢出隐藏	*/
			overflow: hidden;
		}
		a:hover .car{
/*			display: block;*/
            height: 600px;
		}
	</style>
</head>
<body>
	<div class="nav">
		<div class="center">
			<a href="">购物车
                <div class="car">
                	赶紧购买
                </div>
			</a>
		</div>
	</div>
</body>
</html>